#VU8137 Heap use-after-free error in PHP - CVE-2017-12932

Vulnerability identifier: #VU8137

Vulnerability risk: Medium

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2017-12932

CWE-ID: CWE-416

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
PHP
Universal components / Libraries / Scripting languages

Vendor: PHP Group

Description
The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The weakness exists due to improper use of the hash API for key deletion in a situation with an invalid array size. A remote attacker can use untrusted data to trigger heap use-after-free error in ext/standard/var_unserializer.re and execute arbitrary code with elevated privileges.

Successful exploitation of the vulnerability may result in system compromise.

Mitigation
The vulnerability is addressed in the following versions: 7.0.23, 7.1.9 and 7.2.0.

Vulnerable software versions

PHP: 7.0.0 - 7.0.22, 7.1.0 - 7.1.8

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External links
https://bugs.php.net/bug.php?id=74103

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.